Sunday, May 15, 2011


KERENGGA or Weaver Ants (Oceophylla smaragdina) eat any small creatures that they can find but they are particularly attracted to nectar. The weaver ants do not have a stinger, but inflict a painful bite which is aggravated by irritating chemicals secreted from their abdomen. Kerengga or locally also known as 'Semut Merah' in Malaysia normally found in Orchard Farm as a predator to mos unwanted pests that attacked our tropical fruits. Such pests are Fruit Flies (Bactocera spp), Larvae and others. This article I share my knowledge about the use and colony of Kerengga based on my observation as agriculture officer in many parts in Malaysia since 25 years ago.

a) Nest-building

Kerengga nests are among the most complex ants' nests. The ants choose living leaves to build nests at 5-15 meter above grounds. These provide well camouflaged protection from predators and the elements. To create their neat nest, chains of worker ants form along the edge and pull the edges together by shortening the chain by one ant at a time. Once the edges are in place, an ant holds one of their larvae in its mandibles and gently squeezes it so the larvae produces silk. The silk is used to glue the leaf edges together. The larvae have special glands to produce lots of strong silk. The adults do not produce silk. Kerengga lay eggs (in white oblong shape) inside by the 'Kerengga Queens' and local people use the eggs as bait for fishing in local drains.

A colony may be dispersed over several nests which may be placed in various locations in a tree or even span several trees. The queen is located in one nest and her eggs are distributed to the other nests.The ability of simple-minded ants to co-ordinate on such complex tasks is being studied for applications in robotics. If the ants' behaviour could be better understood, simple cheap robots could be built that could achieve complex tasks. The kerengga attack the insects by biting their legs and try to bring to the nests. Other army worker will cooperate to pull the larger insects together with their strong 6 legged kerengga.

b) Role in the habitat:

Kerengga are exploited by plants and animals. Some plants such as the Sea Hibiscus (Hibiscus tiliceaus) secrete nectar in their leaves to attract these ants, which in turn protect the plant from insect leaf eaters. The nasty bite of the ants also discourages larger herbivores. Another plant that does the same is the Great Morinda (Morinda citrifolia). Kerengga nests are often found in these two plants at Sungei Buloh Nature Park in Selangor and many other parts in Malaysia. Some other creatures also exploit the kerengga or Weaver Ant's sweet tooth. Some caterpillars of the Lycaenidae and Noctuidae butterfly families secrete a honey dew that attracts these ants to protect them. Some of these caterpillars are more sinister and use their bribe to gain entry into the ant's nest and devour their larvae! Some jumping spiders look and more importantly, smell like ants, and in their disguise, enter the ant's nest to devour them and their larvae.

c) Status and threats

I found that Kerengga or Weaver Ant eggs (i.e., pupae) are harvested and sold in markets in Thailand and the Philippines but not in Malaysia. The taste of the pupae has been described as creamy. The adults are also eaten their taste has been described as lemony or creamy and sour taste. I never has intention to eat kerengga untill today. This ants are very usefull in Intergrated Pests Management Concepts. Mre colony in an area able to reduce insects pests especiall in commercial orchard farms in Malaysia. The farmers normally burnt with fire to demolish the kerengga nests if they cannot collect or harvest the fruits. The worst thrests came from chemical spraying activities in the farms to kill all psats and insects.

Kerangga has the potential to use as beneficial insects in future. There is not much research done in the use of kerengga as supplementary source of health food yet. May be the saliva of kerengga contains certain chemical that is usefull in curing certain diseases. The avaibality of kerengga in Malaysia may depend on climate, source of food, threats from human and many other factors. I hope there will be a further researchin to study the kerengga technology in future.


By ,

M Anem

Kuala Lumpur



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